Activation and use of hydroalkylation catalysts

Abstract

In a process for activating a hydroalkylation catalyst, a catalyst precursor comprising a solid acid component and a compound of a hydrogenation metal is heated at a heating rate of less than 50° C./hour in the presence of hydrogen to an activation temperature in a range from 100° C. to 260° C. and then the heated catalyst precursor is treated with hydrogen for a duration effective to reduce at least a portion of the metal compound to an elemental form.

The invention claimed is: 
     
       1. A process for activating a hydroalkylation catalyst, the process comprising:
 (a) providing a hydroalkylation catalyst precursor comprising a solid acid component and a compound of a hydrogenation metal; 
 (b) heating the catalyst precursor at a heating rate of less than 50° C./hour in the presence of hydrogen to an activation temperature in a range from 100° C. to 260° C.; and 
 (c) treating the heated catalyst precursor with hydrogen in a temperature range from 50° C. below the activation temperature to the activation temperature for a duration to reduce at least a portion of the metal compound to an elemental form. 
 
     
     
       2. The process of  claim 1 , wherein the heating rate is less than 30° C./hour. 
     
     
       3. The process of  claim 2 , wherein the heating rate is in a range from 1° C./hour to 10° C./hour. 
     
     
       4. The process of  claim 1 , wherein the activation temperature is in a range from 100° C. to 240° C. 
     
     
       5. The process of  claim 1 , wherein hydrogen is supplied during steps (b) and (c) at a GHSV of less than 250 hour −1 . 
     
     
       6. The process of  claim 1 , wherein the treating step (c) is conducted at a hydrogen partial pressure in a range from about 10 kPa to about 10,000 kPa. 
     
     
       7. The process of  claim 1 , wherein the duration of step (c) is in a range from 0.5 hour to 24 hours. 
     
     
       8. The process of  claim 1 , wherein the hydrogenation metal comprises at least one of Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, and Pt. 
     
     
       9. The process of  claim 1 , wherein the solid acid component comprises a molecular sieve. 
     
     
       10. The process of  claim 9 , wherein the molecular sieve comprises a molecular sieve of the MWW framework type. 
     
     
       11. A process for producing a cycloalkylaromatic compound, the process comprising:
 contacting an aromatic compound and hydrogen with a catalyst prepared using a process according to  claim 1  in a hydroalkylation reactor under hydroalkylation conditions effective to convert at least part of the aromatic compound to a cycloalkylaromatic compound. 
 
     
     
       12. A process for producing a phenol and/or cyclohexanone, the process comprising:
 (a1) providing a hydroalkylation catalyst precursor comprising a solid acid component and a compound of a hydrogenation metal; 
 (a2) heating the catalyst precursor at a heating rate of less than 50° C./hour in the presence of hydrogen to an activation temperature in a range from 100° C. to 260° C.; 
 (a3) treating the heated catalyst precursor with hydrogen in a temperature range from 50° C. below the activation temperature to the activation temperature for a duration to reduce at least a portion of the metal compound to an elemental form; 
 (a) contacting benzene and hydrogen with a catalyst prepared by a process comprising steps (a1) to (a3) in a hydroalkylation reactor under hydroalkylation conditions effective to convert at least part of the benzene to cyclohexylbenzene; 
 (b) oxidizing at least part of the cyclohexylbenzene produced in step (a) to produce cyclohexylbenzene hydroperoxide; and 
 (c) cleaving at least part of the cyclohexylbenzene hydroperoxide produced in step (b) to produce phenol and cyclohexanone. 
 
     
     
       13. The process of  claim 12 , wherein the heating rate in step (a2) is less than 30° C./hour. 
     
     
       14. The process of  claim 13 , wherein the heating rate in step (a2) is in a range from 1° C./hour to 10° C./hour. 
     
     
       15. The process of  claim 12 , wherein the activation temperature is in a range from 100° C. to 240° C. 
     
     
       16. The process of  claim 12 , wherein hydrogen is supplied during steps (a2) and (a3) at a GHSV of less than 250 hour −1 . 
     
     
       17. The process of  claim 12 , wherein the duration of step (a3) is in a range from 0.5 hour to 24 hours.